Source : Webster's Revised Unabridged Dictionary (1913)

Bombycid \Bom*by"cid\, a. (Zo["o]l.)
   Like or pertaining to the genus Bombyx, or the family
   {Bombycid[ae]}.

Source : WordNet®

bombycid
     n : moderate-sized Asiatic moth whose larvae feed on mulberry
         leaves and produce silk [syn: {bombycid moth}, {silkworm
         moth}]